The older RPM based distributions, like SLES and CENTOS, use sysvinit as init system. With these distributions the citadel and webcit daemons will be started through the scripts /etc/init.d/citadel and /etc/init.d/webcit. So, you would use

% /etc/init.d/citadel start

to start the citserver daemon.

The newer distributions, like openSUSE, fedora and Mandriva, use systemd as init system. So, you can would use